Taiwanese lefty Wei-Yin Chen has made huge strides since coming to Baltimore as an under-the-radar free agent out of Japan’s professional baseball league before last season.

He's become arguably the most consistent starter in the Orioles' rotation, rarely failing to give his club a chance to win.

But, like he did again Friday in the Orioles' 6-3 loss to the Colorado Rockies, Chen sputtered after the fifth inning, and a seemingly winnable game turned into the fourth straight defeat and fifth in six games for the reeling Orioles (65-56).

"I feel really good today in the early on, especially, I could attack both sides of the plate," Chen said through interpreter Tim Lin. "In the late innings, I felt like I couldn't control the ball in or out. So this is the thing I have to learn. Everything I have to learn, like how to control a ballgame in the late innings."

The Orioles, who hadn't played at Camden Yards since Aug. 4, were coming off a 4-4 interleague road trip out west that included three consecutive walk-off losses and were hoping to get re-energized in front of an announced home crowd of 31,438.

Instead, it was more of the same for the Orioles' offense with Chen on the mound and more of the same for the lefty once his pitch count escalated.

Allowing just one hit through four innings, Chen yielded a run in the fifth on a RBI single by Nolan Arenado before giving up a solo homer in the sixth and a two-run shot in the seventh. He’s permitted eight homers this season and four have come in either the sixth or seventh.

Of the 34 runs Chen has allowed this year, 17 – exactly half – have come after the fifth, including 15 combined in the sixth and seventh (he's pitched just 1 2/3 innings in the eighth and not at all in the ninth this year). In any given inning this year, Chen's ERA does not exceed 2.57 until the sixth when it jumps to 4.97 (in 12 2/3 innings). In the seventh, he has an unsightly 11.37 ERA (over 6 1/3 innings).

Orioles manager Buck Showalter said Chen was a victim of a pesky Rockies team that kept fouling off pitches and an offense that squandered the few opportunities it had.

"They had 30-something foul balls. Who's doing well there, them or Wei-Yin?” Showalter said. "Just not much breathing room for him. He's pitching well. He was working on an extra day's rest today. He pitched well. Whether it's the sixth or seventh or fifth or eight, we're going to have to get other outs. We're going to have to do other things. Wei-Yin was the reason why we were doing as well as we were. We had some opportunities we didn't quite cash in on."

By giving up four runs in 6 1/3 total innings Friday – while allowing just five hits, one walk and striking out seven -- Chen (6-6) snapped his streak of six straight quality starts and eight consecutive outings of yielding three or fewer runs. He’s now lost three in a row.

A lot of it has to do with his offense. The Orioles have scored just 54 runs in Chen's last 22 starts dating back to 2012 – an anemic 2.45 runs a game. They kept the lackluster trend going Friday, getting just three runs against Colorado’s Juan Nicasio (7-6) and three relievers.

"It's cyclical. People aren't going, 'Who's pitching for us tonight? Oh, gosh, we feel pressure.' I don't think it changes, the mentality of it,” Showalter said about his club’s inability to score for Chen. "There always seems to be somebody. But Wei-Yin's throwing the ball well. We all know he's deserving of a little bit better fate."

The Orioles scored first – and quickly. Nate McLouth led off the bottom of the first by hitting Nicasio’s third pitch over the right-center wall for his eighth homer of the season. McLouth now has 12 career leadoff homers, including two this year.

They made it 2-0 in the third when Nicasio, making his first career start against the Orioles, loaded the bases with one out on two walks and a single. Adam Jones followed with an opposite-field grounder into right, snapping a 0-for-15 skid.

The Orioles couldn’t do more damage in the inning -- with Nick Markakis and Matt Wieters stranding the three runners – or in the game until the ninth, when Wieters homered for the 17th time this season. The Orioles went hitless in five consecutive innings and, for the first time this season, the Rockies (58-65) won on the road after their opponent scored first.

“Chen goes out there and gives us a great chance every time,” Jones said. “It's unfortunate we're not able to score more runs for him, but that's part of the game sometimes.”

Down 2-1 in the sixth, Colorado left fielder Charlie Culberson smacked his first big league homer to tie the game. In the seventh, Wilin Rosario took Chen deep with a two-run shot. It was the second of four homers allowed by the Orioles on Friday – padding their big-league lead of 156 homers served up.

Charlie Blackmon homered onto Eutaw Street in the eighth against reliever Francisco Rodriguez, who left the game one batter later due to a strained right groin and will be re-evaluated Saturday. It was the 73rd home run in stadium history that has landed on the street behind the right-field flag court and first by a Rockie.

“They'll put a plaque out there with your name on it. There are not a whole lot of plaques with my name on it going up anywhere. I think that would be something really cool,” Blackmon said. “I wouldn't have expected me to be one of those guys."

In the ninth, veteran Todd Helton homered against struggling closer Jim Johnson, who was trying to pitch out of his recent funk.

Instead, the Orioles continued their August funk – they are now 6-7 in the month.

But the Orioles contend they aren’t worried about falling out of the pennant race.

“The team is fine. We lost. I think this is honestly something that we needed, kind of a kick in the pants to wake us up,” Jones said. “We’re in a unique position, in back to back years trying to do something special. Last year, everybody said we couldn't. This year, we created the expectation. This is something you've got to go through to get to it. The adversity, I think, this ballclub needs because most of us in here have overcome a lot of adversity, and collectively, I think we can do it again.”

The Orioles optioned outfielder and designated hitter Henry Urrutia to Triple-A Norfolk following Friday night’s 6-3 loss to the Colorado Rockies. Manager Buck Showalter said after the game the Orioles will probably bring up a bullpen arm because of right-hander Francisco Rodriguez’s strained right...